sister slap 

A sister slap is a slap that may be administered by an older sister to a younger sister, when said younger sister is acting a fool

Yo, my younger sister got a speeding ticket so I gave her a sister slap...across her face

sister slap by Louroo October 20, 2013

Sister slap 

When someone wants to slap someone but they’re too close to you so you don’t.

I want to sister slap my best friend but she’s my bestie so I can’t.

Sister slap by itchyboa January 24, 2019

National Slap Your Sister Day 

On October 25th you can slap your sister all you want and you won’t get in trouble.

Hey why is your sister crying

Because I slapped her for National Slap Your Sister Day

National Slap Your Sister Day by boppotheclown October 24, 2020

National slap your sister day 

July 24 you can slap your sister

Hey its national slap your sister day, go ahead.

National slap your sister day by alpha alpha alpha July 24, 2021

National slap your sister day 

Slap your sister today!

July 24th

National Slap your sister day is today!

National slap your sister day by Himynameiskyle July 24, 2021

National Slap Your Sister Day 

On the 10th of August, after National Slap Your Brother Day, is National Slap Your sister day. It is a day where you, as it says in the title, a day to slap your female siblings.

Me:"It's National Slap Your Sister Day"
My sister: Shit...

National Slap Your Sister Day by EpicCommie August 9, 2021

sister slapper 

When you live in Alabama and have incestual interactions with your sister.

You must be a sister slapper because you and your sister had sex last night!

sister slapper by EVIL Ma January 12, 2019